The present invention relates to improvements in the take-up spool which winds up a correction tape for lifting off mistyped characters from a paper by means of the adhesive material applied on the correction tape for a typewriter.
The correction tape is generally used in such a manner that the free end of the correction tape wound on a bobbin is extended to the reel portion of a take-up spool and the take-up spool is rotated intermittently by means of the typewriter mechanism to take up the correction tape on the reel portion of the take-up spool.
In a conventional arrangement, as shown in FIGS. 1 and 2, a bobbin 2 on which a correction tape 1 is wound is cylinder-shaped and has helical slits 4 over the circumference of the bottom portion thereof. The bobbin 2 is mounted rotatably on the holding shaft (not shown) of typewriter mechanism so that the helical slits 4 of the bobbin 2 are in mesh engagement with the spring member (not shown) secured to the holding shaft, whereby the free rotation of the bobbin 2 in the direction of arrow a is hindered to ensure a proper tape tension.
A take-up spool 3 has a tape reel portion 7 at the intermediate portion thereof defined by an upper flange 5 and a lower flange 6; a knob 8 on the upper flange 5; a ratchet gear 9 formed at the bottom of the lower flange 6; and an engaging hole 10 formed extending from the central portion of the ratchet gear 9 to the inside of the reel portion 7. The take-up spool 3 is rotatably mounted on the holding shaft (not shown) of typewriter mechanism so that the holding shaft is inserted into the engaging hole 10. The ratchet gear 9 is brought into mesh engagement with the jaw clutch (not shown) of a typewriter mechanism, whereby the spool 3 is rotated intermittently.
With the conventional bobbin 2 and spool 3 for the correction tape 1, since their rotation mechanisms are significantly different from each other as described above. it is not allowed to exchange the supporting position of the bobbin 2 for that of the take-up spool 3 for reusing the correction tape 1 as in case of ordinary typing ribbon spools. Thus, the correction tape 1 is a throwaway one in the conventional technique. If it is desired to reuse the correction tape 1 for economy's sake, the correction tape 1 wound up on the spool 3 must be manually re-reeled on the bobbin 2, requiring a laborious procedure.
It is an object of the present invention to provide a correction tape take-up spool for typewriter which is constructed so that the correction tape can be reused without re-reeling the correction tape wound up on the spool on a bobbin.
This and other objects of the present invention will become apparent from the description hereinafter.